Ingot mold



United States Patent O y INGOT MOLD Mark H. Gathmann, Chicago, lll., assignor to United States Steel Corporation, a corporation of New Jersey Application February 19, 1957, Serial No. 641,186 4 Claims. (Cl. 22-139) This invention relates to big-end-down ingot molds and more particularly to such molds having interior walls formed with vertical corrugations, utes or ripples.

These corrugations have a tendency to produce an erosion and cracking on the bottom of the mold in the ingot forming chamber when the mold is supported on a flat stool. The molten steel as poured ows andsurges against the bottom of the mold wall and the corrugated sections of the mold form stops or baffles which I believe is the cause of the fast erosion of the mold walls at this point. The apexes of the corrugations form a nucleus for the starting of cracks which progress, with the number of ingots cast, from the inside of the bottom section of the mold wall to the outside surface of the ingot mold wall. These. cracks ll with molten steel which when solidied produces a pull or binding action against the sections between cracks. This causes a break or pull out of mold iron from the bottom section of mold wall, thus decreasing mold life. It has also been observed that cracks of this type grow in length and cause serious tins to be produced on ingot surfaces. These tins cause an increase in scarng and chipping costs when conditioning the ingots.

It is therefore an object of my invention to provide a big-end-down corrugated ingot mold having a plain interior wall area at its bottom portion for the purpose of increasing the life thereof.

Another object is to provide a big-end-down corrugated ingot mold which will produce ingots having fewer tins on their side surfaces adjacent the bottom thereof.

These and other objects will be more app-arent after referring to the following specilication and attached drawings, in which:

Figure 1 is a view, partly in section, of a big-end-down mold mounted ou a stool;

yFigure 2 is a side view, partly in section, of the mold of Figure 1;

Figure 3 is a top plan view ofthe mold of Figure 1; and

Figure 4 is a bottom plan view of the mold of Figure l.

Referring more particularly to the drawings, reference numeral 2 indicates the stool on which a mold 4 is vconstruction so far described is conventional.

Patented Feb. 3, 1959 ICC mounted. The top surface of the stool 2 is at as shown. The interior wall of the mold 4 has vertical corrugations, utes or ripples 6 therein. The inner walls of the mold 4 taper downwardly and outwardly with the w-alls of the mold being thicker at the bottom than at the top. The In my invention I provide a plain interior wall area for a distance A at the bottom of the mold. Distance A is at least four inches in height and is preferably no more than ten inches high in a standard mold which may be approximately eighty-four inches high. The inner wall at this point slopes upwardly and inwardly and is connected to the main corrugation 6 by means of a transition wall area having a height B which is preferably at least six inches. This transition wall area is formed by the lower ends of the corrugations gradually tapering downwardly and outwardly to merge into the plain lower Wall area. The combined height of the plain and transition wall area, that is, the distances A plus B, is no more than one-fourth the total height of the mold. Because the plain wall area starts at the bottom of the corrugations 6 the bottom wall of the mold is thinner than the adjacent wall. While it is preferred to have the entire periphery of the bottom wall area plain, good results can be obtained when only two sides of the bottom wall are plain.

While one embodiment of my invention has been shown and described it will be apparent that other -adaptations and modications may be made without departing from the scope of the `following claims.

I claim:

l. A big-end-down ingot mold having an interior wall formed with vertical corrugations of substantially uniform dimensions, the interior wall of the mold being plain for a distance of at least four inches from its bottom with the surface thereof being in substantially the same plane as the bottom of the corrugations, the lower ends of saidy corrugations being gradually tapered downwardly and outwardly and merging Iinto said plain wall.

2. A big-end-down ingot mold according to claim 1 in which the combined height of the plain and merging wall area being no more than one-fourth the total height of the mold.

3. A big-end-down ingot mold according to claim l in which the height of the plain wall is between four and ten inches. v

4. An ingot mold assembly including a stool having a flat top surface and a big-end-down mold resting on said ilat top surface, said big-end-down mold having an interior wall formed according to claim l.

References Cited in the tile of this patent UNITED STATES PATENTS 

